Impulse-transmitter.



W. F. HOFFMANN.

IMPULSE TRANSMITTER. APPLICATION FILE]; MAY 26, 191i.

' Patented Jan. 5; 1915.

3 SHEETS-SHEET 1.

3 n ve-m to W. F. HOFPMANN.

V IMPULSE TRANSMITTER.

APPLICATION FILED MAY 26. 1911.

Patented Jan. 5, 1915.

a SHEETS-SHEET z.

W. P. HOPFMANN. IMPULSE TRANSMITTER.

APPLICATION FILED MAY 26. 1911.

1 1 24,02 1. Patented Jan. 5, 1915.

3 SHEETS-SHEET 3.

38 6 I Q l4 30" L 37 35 8/ a g l a 5 a4 ,yMW; v alloy nu,

tions are-likewise applicable to other -elec-- i ating lever.

STATES WILLIAM F. HQFFMANN, or sPRINeFInLn,

COMPANY, on NEW YORK, N. Y., A CORPORATION or ILLI- 'ro WESTERN ELECTRIC NoIs.

To all whom z'tmay concern:

Be it know-nthat I, WILLIAMF. Horn MAN N, a citizen of the United States, residing at Springfield, in'the county of Clark and State of Ohio, have invented certain new and useful Improvements in Impulse- Transmitter's, of which the following is a specification.

This invention relates to impulse transmitters for electric circuits, and it particularly relates to improvements in calling devices usedin Connection with automatic telephone systems; although the constructrical systems s'uch'as'fire alarms, telegraph and the like. I

The objectof the invention is to simplify the construction and make more effective the operation of devices of'this character.

The invention consists in the constructions and combinations of parts hereinafter described and set forthiinthe claims.

In the accompanying drawings: Figure 1 is a top plan viewv of a deviceembodying the invention. Fig. 2 is a bottom plan view of the same. Fig. 3 is a section on the line az-w of Fig. 5. Fig. 4 is a detail view of one of the keys. Fig. 5 is a rear elevation of the device. Fig. 6 is a section on the line y-y of Fig. 5. Fig. 7 is a detail view in perspective ofthegraduated oper- Fig- 8 is a side elevation of the device looking from'the front. Fig. 9 is-a vertical section on the line z2 of Fig. 1. Fig 10 isaverticalfsection in detail of the governor, thesection being on the line b,?) of Fig. '11. Fig- 1-1iS a transverse section of the governor on theline H of Fig.

10. Fig. 12 is a perspective view of apertion ofthe mechanism. of the manner of Itlransmitting the motionfrom the operating eys. 7

Like parts are represented by similar charactersof reference in the several views.

In" theembodiment of the invention as shown in the drawin s, a frame work is, provided consisting 0 an upper and bottom pla'tefl and 2 and a central-plate 3, cir

' cularjijn formand spaced apart and connect- 1n ing haft hayingconnected therewith just ed together by-posts 4, 5jand 6. Journ'aled 'theirame partSl. 2.and 3 is a main drivi beneath tli'elbiittomplate[2' one end of a coil spring 8, the bl'iliifr endof said spring being ,.fastened a.fdownwardlyprojecting pin -9 tactingthe lower side of the top plate 1 so Specification of Letters Patent.

OHIO, ASSIGNOR, BY MEsN'E ASSIGNMENTS,

. IMPULSE-TRANSMITTER.

Patented Jan. 5, 1915. 1911. Seria1No.629,581.

on said plate 2. Secured to said shaft 7' by a set screw 11 between the plates 2 and 3 is .a -ratchet Wheel 10. J ournaled loosely on the shaft 7 is a gear 12, carrying a springpressed pawl 13, (Fig. 6) adapted to. engage with the teeth of the ratchet wheel 10 so as to'cause'the gear 12 to revolve in one direction therewith but permit said ratchet wheel to movefreely in the opposite direc-'v tion. 4 v p J ournaled looselv in bearings '14 and 15 secured respectively 'to the upper side of the frame-plate 3 and the lower side of the frame plate 2, is an arbor 16, geared to the main gear 12 .through the medium of a pinion 17 -on saidarbor; gear 18on a shaft 19 journaled loosely in Said frame plates 2 and 3; pinion 20 on said shaft 19; 'gear 21 on a Second shaft 22 also journal'ed in said frame p1ates,"and a pinion 23 on Said shaft 22 meshingwith said gear 12; the proportion of the gearing being preferably such that a movement the distance of one notch of said-ratchet wheel 10 will impartone complete revolution to the arbor 16.

Secured to the lower end of the arbor 1.6

just beneath the frame plate 2 is a cam disk.,24, the high part of which," upon each revolution of the arbor, isadapted to strike the block 25, of insulating material, on a spring strip 26 which forms one member of the circuit breaker, the other member being stationary and represented by. reference character 27. The respective members '26 and 27 ofthe circuit breaker are secured to the underside of the frame plate 2jby screws .28 and 29, and are spaced apart and fromv the plate 2 by blocks 30 of insulating-ma terial,"and are provided at their outer ends with contact points 31 a'nd'32. I In thepresent instance the construction is such that the contacts are normallyv closed.

Secured to the upper end of the main a b ock 38 on the key-Stem.-34:;-' said fblocks 38.also Serving as stops for the keys by conas to limit the upward movement of said keys. Means are provided for causing the respective keys, when depressed, to impart varying movements to'the operating arm 33 and hence to the operating mechanism. The preferred form for accomplishing this is shown in Figs. 3 to 9 inclusive. Located upon theouter edge of the operating arm 33 is a series of ten inclined surfaces or projections a, a a a, a a, a, a a", and 0, arranged at varying distances from the center of rotation of said arm, one projection being adapted to cooperate with each key. J ournaled on each of the blocks 38 is a friction roller 39 which normally stands just above the inclined projection on the arm 33 corresponding thereto. 1 The inclinations of the respective surfaces are such, having due regard to theirv distances from the shaft 7. that the depression of the keys will impart varying movements to the arm 33, this movement gradually increasing from the key marked 1 to the key marked 0. The surfaces on the arm are arranged at different inclinations or angles. This has been done for the purpose of incorporating the mechanism into small compassit being obvious that if the projections were at uniform progressive distances from the center of rotation, the inclinations or angles might all Y be the same.

In Fig. 12 there is shown a modification of the manner of transmitting .the movement of the keys to the operating arm 33. In this modified construction, instead of having graduated projections on the arm 33, the key stems are provided with blocks 46 having inclined surfaces adapted to contact the serrated edge 47 of'the arm 33, the inclination of the inclined surfaces of the blocks being suitably graduated so as to cause the depression of the keys to impart varying'movements to the operating mechaplate iet secured to the arbor 16. When the revolution of the arbor exceeds a certain speed these arms will by centrifugal force be vthrown into contact with the inner 'wall of a casing 45 so as to act as a friction brake and thus maintain a uniform "speed.

In the operation of thedevice, the calling subscriber depresses the keys corresponding to the number of the telephone with which he desires to connect. If, for instance, the

key 3 is depressed, upon the depression of said key the contact of the' friction rollerwith the projection a will rotate-the lever '33, and hence the main driving shaft, a distance corresponding in the present case to the movement of three notches, in theratchet Wheel 10. This movement of, the operating lever also causesthe stop 41 to release the detent 40 so that when the operatorreleases the depressed key 3 and it returns .to-its normalposition by its spring, the main spring 8 willcause the shaft 7 to rotate back to its normal position. This return movement of the main shaft causes the arbor 16 which carries the cam 24, to be given three complete revolutions through the medium of the train of gearing described, so that said cam will cause the circuit breaker to open and close the circuit ree successive times and thus send three successive impulses over the circuit. The stop 41 and detent 40 are so dis posed with respect to each other that the revolution of the parts will be checked at the end of the third revolution of the arbor. In like manner now, if the-6 key is next depressed, the inclination and disposition of its projection a is such that the parts will be rotated a distance corresponding to, six notches of the ratchet wheel, and cause the cam on the-arbor to be g'ven six complete revolutions upon the I eturn movement of the parts, thus sending six impulses over the circuit. After one of the keys 35 has been depressed it will of course be necessary that such key be permitted to return to its normal position before another key is depressed; To insure this, there is provided an index hand :18 (Fig. 1) connected to the upperend' of the shaft 7. This index hand normally'jstands at a zero indication, and as said shaft revolves it Will be moved from its normal zero position a distance to;correspond to the key depressed and will be returned tothe zero indication when the parts are returned -t o their normal position. It will be seen that the operator by observing this index hand may tell when the parts have been fully returned to their normal positionand .be'in proper condition for the operation of the next key. I

Having thusdescribed my aginvention, I claim: a

1. In an impulse transmitter, circuit terminals, operating mechanism jtherefor comprising a movable member, a seriesjof contact surfaces" on said member,a nd a series of actuating devices each having means cooperating with one o nly gofthexsurfaces of.

said movable member -w'hereby 'said 'actw"; 'ating' devices will, impart va ing, degreesof movement to said'movable member...

2. In an impulse' tiansmitter, circuit'tii' minals, an operating mechanism therefor -COmPI'ISIHg a movable arm havmg a ser of projections, and a series of actuating devices each having means coeperating with one only'of said projections whereby said actuating devices will impart varying degrees of movement to said movable member. I

3. In an impulse transmitter, circuit terminals, operating mechanism therefor comprising a' movable member, a series of projections on said member, and aseries of actuating devices each having surfaces cooperating with one only of the projections of said movable member whereby said actuating devices will impart varying degrees whereby said cam is given a varying movement determined by the actuating device operated.

5. In an impulse transmitter, the combination, with the circuit terminals, of a spring actuated shaft, an operating arm connected to said shaft, a rotatable cam geared to said shaft and coeperating with said circuit terminals, the proportion of the gearing being such that a partial rotation of said shaft imparts oneor more complete revolutions to said cam; and a series of'actuating devices coeperating with said arm for imparting varying rotary movements to said shaft whereby said cam is given a varying number of complete revolutions determined by the actuating device operated.

6. In an impulse transmitter, the combination, with the circuit terminals, of a ro-.

tatable shaft, a rotatable cam geared to said shaft so as to rotate therewith in one direction only and cooperating with said circuit terminals, the proportion of the gearing being such that partial rotation of said shaft will impart one or ,inore complete revolutions to said CflIH, an arm connected with said shaft, a series of actuating devices cooperating with'said arm to impart varying rotary movements to said shaft, and a spring for returning said shaft to normal position, substantially as specified.

7. In an impulse transmitter, a rotatable shaft, a rotatable spindle geared to said shaft so as to rotate therewith in one direction only, the proportion of the gearing being such that a partial movement of said shaft will impart one or more complete revolutions to said spindle, circuit terminals, a cam on said spindle, coiiperating with said terminals, an arm OIiSaId shaft,a series of actuating devices cotiperatmg with said arm to impart varying partial movements to said shaft, a spring for returning said shaft to normal position, and pro ections on said arm and spindle coiiperatmg with each other to arrest the movements of said parts, substantially as specified.

8. In an. impulse transmitter, the combination, with the circuit terminals, of opcrating mechanism cooperating with said terminals, said operatingmechanism comprising a movable arm having a series of contact surfaces, and a series of actuating devices also having a series of contact surfaces each coiiperating with one only of the contact surfaces of said arm, so arranged as to cause said actuating devices to impart varying movements to said arm whereby said terminals are opened and closed a varying number of times determined by the actuating device operated. v

9. In animpulse transmitter, the combination,"with the circuit terminals, of an operating mechanism coilperating with said terminals, said operating mechanism comprising a movable arm having a series of contact surfaces, a series of actuating devices also having aseries of contactsurfaces each cooperating with one only of the contact surfaces of said arm, one series of contact surfaces being graduated so as to cause said actuating devices to impart varying movements to said arm whereby said circuit terminals will be opened and closed a varying number of times determined by the'actuating device operated.

10. In an impulse transmitter, the combination, with the circuit terminals, of an operating mechanism coiiperating with said terminals, said operating mechanism comprising a movable arm having aseries of contact surfaces, a series of actuating devices arranged at right-angles to said arm also having a series of contact surfaces coiiperating with the contact surfaces of said arm and arranged to impart varying movements to said arm,-andmeans for returning said arm to normal position.

11. In an impulse transmitter, the combination, with the circuit terminals, of an operating mechanism coiiperating with said terminals, said operating mechanism comprising a rotatable arm havinga series of inclined projections arranged at varying distances from the center of rotation of said arm, and a series of actuating devices having contact surfaces coiiperating with said inclined projections, substantially as specified.

12. In an impulse transmitter, the combination, with the circuit terminals, of an operating mechanism coiiperating with said terminals, said operating mechanism, comprising a rotatable arm having a series of contact surfaces arranged at varying distances from the center' ;of rotation of said arm, a series of spring-pressed keys arranged at right-angles to said arm, one key I .for each contact surface, and a contact surfaceon each of said keys coiiperating with its corresponding contact surface on said arm whereby upon the depression of any key said arm will e moved a distance corresponding to the key operated, and means for returning said arm to normal position. 13. In an impulse transmitter,-the combination with the circuit'terminals, of an operating mechanism coiiperating with said terminals, said operating mechanism comprising a rotatable arm having a series of contact surfaces, arranged at varying distances from the center of rotation vof saig arm, a series of spring-pressed keys arrange at right-angles to said arm, onekey for each contact surface, each of said keys having a,

friction roller adapted to cooperate with its corresponding contact surface when! said key is depressed so as to move-said arm a distance determined by the position .of said j contact surface, and means for returning-J 7 associated tiierevvith, a series of push buttons having shanks" passing through said plate, and connections between each of'saidr said. arm to normal position.

14. In an impulse transm tter, the com-:-

bination, with the circuit terminalsyoffan operating mechanism cooperating W thsaidterminals to'open and'close the same, a seriesv of actuating devices cooperating vvith said operating mechanism to cause the samei'to be moved varying distances to open and closefsaid terminals a" varying number of times determined by the operated actuating device, means for. return ngsaid operating mechanismto normal position, and anindicator for indicating the position of said I mechanism, substantially as specified,

15; In an. impulse transmitter, asupporting plate, circuit terminals, operating mechanism thereforcomprisinga; movable plate substantially parallel to said supporting plate, a series of push buttons having shanks passing through saidsupportingplate, and operable connections between sa d buttons and said movable plate whereby the depres:

sion of said buttons will impart varying. de grees of movement to said movable plate according 'to the button depressed.

16. In an impulse transmitter, a pair of corresponding to the abiitton depressed.

mahoai supporting plates, circuit terminals; ope rat mg mechanism therefor comprisinga movable plate substantially parallel to'said supporting plates, a series of push buttons having shanks passing through said supporting plates, and operable connections between said buttons and said movableplate Whereby the depression of said buttons will impart,varying degrees of movement to saidplate 'whereby. the depression 'of said buttons will impart varying degrees of movement to said movablegplate according to the button depressed.-

18, In an impulsetransmitter, a supporting plate, circuitterminals, operating mech anism therefor, a series of contact surfaces buttonsand one} only of said contact s'urfaces wherebythe depression of said but-' tons Willvariously actuate, said mechanism to cause said: circuit terminals to beclosed a numberof time's corresponding to the button depressed.

19. In an impulse transmitter, a support-.

ing disk, circuitterminals, operating mechthrough, and connections between said but-' tons and said operating mechanism whereby the depression of saidbuttons Willvariously actuate saidmechanism to cause said circuit terminals to be closed a number of times In testimony whereof, I have hereunto so my hand'this 8th day of May 1911. y a, WILLLAllfI F. HOFFMANN.

1;Witnesses: 1 Y

I 4 Cnas; I. WELcn,

' I -ELSA K. SMITH.

. Ibo 

